Bemoaning decline in a different time, George Orwell once said we “have sunk to a depth at which the restatement of the obvious is the first duty of intelligent men.” Happily for readers interested in the state of the nation, Mark Steyn has reported for duty.

As in his previous outing “America Alone: The End of the World as We Know It,” in “After America: Get Ready for Armageddon,” Mr. Steyn has written a very serious book. Throughout, he braces readers with quite a lot that should be obvious, yet is overlooked by many who willfully avert their gaze. He advises us at the outset that “America Alone” was “about the impending collapse of all of the Western world except America.” In “After America,” he laments having to report that America “has decided to sign up for the same program but supersized.” And he hopes that Americans will rediscover their historic strengths, seize the throttle and pull their country out of its current tailspin.

Given that the downgrading of America’s credit score by Standard & Poor’s roughly coincided with the launch of this book, it’s amusing (but hardly surprising) that the prologue is titled “The Stupidity of Broke.” Upfront we are introduced to a raft of unhappy information about our nation’s unsustainable spending and borrowing habits. Soon our interest payments on the national debt will exceed what we spend on defense, and by the way, those same payments will fund the entire military (somehow I don’t think “defense” is the right adjective) budget of the People’s Republic of China. With characteristic understatement (well, not really) Mr. Steyn observes that when “the Commies take Taiwan, suburban families in Albuquerque and small businesses in Pocatello will have paid for it.”

While Mr. Steyn gives the current administration credit for doubling down on deficit spending, he’s appropriately bipartisan in assigning responsibility for the decades-long run-up to the current crisis. As he notes, before “the Democrats accelerated to Obamacrous Speed in 2009,” the government spending graph had been “a near perfect straight line across four decades, up, up, up” - without regard to which party controlled the White House and the Congress.

In one generation, Mr. Steyn observes, “a nation of savers became the world’s largest debtors, and a nation of makers and doers became a cheap service economy.” If that overstates the situation, it does not miss the fundamental point, and Mr. Steyn documents in excruciating detail (with 50 pages of footnotes following the text providing backup) our descent into a “multitrillion-dollar debt catastrophe” accompanied by “increasing dependency, disincentivizing self-reliance, [and] absolving the citizenry from responsibility for their actions.” This is all brought to us by the core problem, what he terms “the remorseless governmentalization of American life.”

As he chronicles the dependency agenda of our leadership, with rich parallels to current-day Greece and the United Kingdom, Mr. Steyn also points to a moral failing, a deliberate abdication of leadership and greatness. Yes, our debt as a percentage of gross domestic product was slightly larger in 1945 than it is today, but that was “after a world war in which [America] vanquished mighty enemies of global reach and established itself as the dominant power on the planet.” What do we have to show for our debt today? Unsustainable entitlements, global economic and military decline and a new class war in which “takers” in unions and among our “pubic servants” and the permanently dependent face off against “the rest of us.”

Within a decade, not so long ago, we put men on the moon and the first to arrive had the “insouciant swagger” to salute the world by playing Frank Sinatra’s “Fly Me to the Moon” on a portable tape player. Today, NASA’s administrator explains President Obama’s charge that the space agency should “reach out to the Muslim world” in order to “help them feel good about their historic contribution to science and math and engineering.”

Mr. Steyn’s sendup of such nonsense is marvelous: “Islam: The final frontier! To boldly go where no diversity outreach consultant has gone before!” As for making Muslims “feel good” about their contributions to science, he dryly notes that “as recently as the early ninth century” there was a notable achievement. But “things have been a little quiet since then.” So, even as the author brings us bundles of bad news, he’s polite enough to do so with panache, with prose that is succinct, lucid and entertaining.

In the final analysis, happily, he offers hope. He notes that only in America have people taken to the streets to ask the government to do less. But he urges that time is of the essence, and that a statist America will be more like the Third World than Sweden. He is persuasive and, because his good humor and good will permeate, he can be read and enjoyed by readers of all political stripes. He is a messenger we should thank.